1. Field of the Invention
The present disclosure relates to an image forming apparatus.
2. Description of the Related Art
An image forming apparatus that uses an electrographic system, such as a copier, a printer, a facsimile, or a multi-functional peripheral thereof includes an image bearing member, a charging device which uniformly charges the surface of the image bearing member, an exposure device which forms an electrostatic latent image on the surface of the image bearing member by exposing the surface of the charged image bearing member, a developing device which develops the electrostatic latent image as a toner image by supplying toner to the surface of the image bearing member on which the electrostatic latent image was formed, a transfer device which transfers the toner configuring the toner image from the image bearing member to a recording medium, and a fixing device which fixes the transferred toner image to the recording medium by heating and pressuring it. This kind of image forming apparatus forms an image on the recording medium by using the respective devices described above by forming a toner image on the image bearing member, transferring the toner image to the recording medium, and thereafter fixing the toner image on the recording medium. After the toner is transferred onto the recording medium, the toner remaining on the image bearing member is removed from the image bearing member by a cleaning device having a cleaning blade or the like which comes in contact with a photoreceptor drum that serves as the image bearing member.
The developing device that is provided to this type of image forming apparatus that uses the electrographic system is disposed opposite to the photoreceptor drum as the image bearing member, includes a toner bearing member (development roller) which bears the toner on its surface and thereby conveys the toner, and supplies the toner that was conveyed by the development roller toward the peripheral surface of the photoreceptor drum on which the electrostatic latent image was formed. Consequently, the developing device forms a toner image on the photoreceptor drum.
This kind of developing device is demanded of superior toner conveying performance by the development roller. In order to improve the toner conveying performance, as the development roller, the use of a roller that is subjected to treatment for forming irregularities on the surface of a metal roller is known.
As this kind of development roller, for example, the following rollers are known.
Foremost, as a first example, there is a powder bearing member in which the surface layer is at least made from an aluminum material, and an alumite treated layer is formed on the surface after being subjected to sandblast treatment.
Moreover, as a second example, there is a cylindrical developer bearing member including an alumite layer coated on a conductive substrate surface that was subjected to uniform roughening, and in which the alumite layer includes uniform micropores that reach the substrate surface.